Conventionally, a maximum data rate used by a network could be closely related to the quality of service (QoS) parameters. FIG. 1 illustrates a reference network architecture used by a 3GPP Evolved Packet System (EPS). Under this network architecture, the mobility management entity (MME) 101 would suggest QoS parameters which may include a maximum data rate to a serving gateway (S-GW) 104, and the QoS parameters may be transmitted from S-GW 104 to a packet data network gateway (P-GW) 102. The P-GW 102 may then authorize the QoS parameters to the S-GW 104, and the authorized QoS parameters may be transmitted from S-GW 104 to the MME 101. The MeNB 103 may then control the allocation and utilization of radio resources to maintain the authorized QoS parameters.
FIG. 2 illustrates a signaling diagram for configuring the maximum data rate of a communication system. For the communication system of FIG. 2, the downlink (DL) and uplink (UL) maximum data rate is decided when a packet data network (PDN) connection, which is the connection between a user equipment (UE) and a P-GW, has been set up. The phrase ‘PDN connection’ could be synonymous with the phrase ‘PDU session’ which is used predominately in a 5G network. Mobile communications has evolved towards the integration of radio access technologies and the aggregation of radio resources for UEs in order to achieve the high data rate and high capacity requirements of a next generation of a mobile communication system. For example, the mobile communication systems may utilize licensed and unlicensed spectrum for providing communication services to users to enhance the throughput. However, the available radio resources for a UE may vary drastically when the UE is moving. For example, when a UE served by a low frequency radio access node moves into the coverage of an overlaid high frequency radio access node that could support high data rate transmission, the UE may utilize the radio resources of both low frequency (e.g. RF frequency) and high frequency (e.g. mmWave) radio access nodes. When the UE moves out of the coverage of the high frequency radio access node but still served by the low frequency radio access node, the available radio resource of the UE may decrease dramatically.
To reflect the variation of the available radio resources for a UE, the maximum data rate control function within the future network would still be needed to ensure that the maximum data rate as required by the authorized QoS parameters are maintained. The resource management function within the future network could be responsible for how the resources are distributed in the access network based on the authorized QoS parameters from the QoS operation control function as well as the monitoring of the fulfillment of the QoS targets. The resource management function could be different between a 3GPP and a non-3GPP standard with regard to the possibilities to control resource utilization and resource availability.
FIG. 3 illustrates QoS configuration in a 5G QoS framework from the perspective of a control plane. According to 3GPP TR 23.799 v.1.0.2, one candidate implementation of 5G QoS framework could be to have QoS parameters assigned to a PDU flow distributed by the core network control plane (CN_CP) to the core network user plane (CN_UP), the 3GPP access network and optionally the UE, and are enforced by the network functions such as by CN-UP, access network, and optionally UE. The QoS parameters would impose a required data rate per PDU flow which is required for the service to be delivered with sufficient QoS. The required data rate per PDU flow would be used by the access network which would tries to uphold the required data rate.
In FIG. 3 for example, the radio access network (RAN) 301 and the core network control plane function 302 would uphold the DL/UL QoS configuration which would include the maximum data rate, and the core network user plane function 303 would dispatch the DL/UL QoS rule and parameter to the RAN 301 and the core network control plane function 302. When the access network cannot satisfy the required data rate, the access network may either drop the packet or to provide a best effort service with or without any signaling to the core network based on the network behavior per PDU flow. A QoS rule may include the information of QoS rule identifier, QoS class identifier, the DL and/or UL maximum data rate, the DL and/or UL guaranteed bitrate, the priority of a QoS rule, flow detection and filtering information. QoS parameters may include the QoS class identifier, the DL and/or UL maximum data rate, the DL and/or UL guaranteed bitrate, the number of allowed DL and/or UL packets in a specific time duration, and the priority.
In general, a mechanism to dynamically adjust the maximum data rate according to the available radio resource could be needed.